(Yicai Global) Aug. 1 -- Chinese and American researchers recently allied to develop a nanoparticle vaccine that protected mice against influenza A virus in experiments, state Xinhua News Agency reported.

A study published July 39 in the Proceedings of the National Academy of Sciences shows that the two-layered vaccine made with polypeptides mimics the biological cues of viruses and initiate danger signals that activate double immune responses.

"The double-layered nanoparticle has a core made of polypeptide from nucleoprotein, an internal influenza protein that produces cross-protection against influenza virus by inducing T-cell immune responses; in addition, it also triggers an immune response in B lymphocytes and synergies with immune T cells," one researcher said.

Polypeptides are intermediates in the process of protein hydrolysis which are much smaller than proteins.

The nanoparticle inoculants are delivered by skin vaccination with a dissolvable microneedle patch rather than intramuscular injection, making the vaccine more potent and with longer-lasting immune effects.

Researchers from Georgia State University, Georgia Institute of Technology, Emory University and China's Henan Normal University hope to develop a universal flu vaccine with stronger efficacy and a better route of administration on this basis, one which can resist a variety of flu viruses, they said.